1. Field of the Invention
This invention relates to a process and the products produced thereby for the reuse of scrap material which at the present time has little or no commercial value.
2. Description of the Prior Art
In recent years it has become apparent that it is necessary for man to recycle and reuse materials which he had previously simply discarded as trash. It has also become necessary in recent years, both from environmental and economic considerations, to find uses for many of the waste products produced by our industrial processes. One of the largest single by-products produced by industry is the slag which is formed in the refining of ores and metals and in the burning of carbonaceous fuels. The steel industry has long recognized that it would be desirable to find a use for the many millions of tons of slag which it generates every year. Toward this end, it has been suggested that slag can be used as railroad ballast, in the manufacture of cement, as fill, as aggregate for roads, as aggregate for cement products, in roofing material and the like. While the steel industry is able to dispose of many tons of slag each year for such uses, the percentage of slag which is placed into commercial application is very small when compared to the total quantity of slag produced. A familar sight around any steel mill is the huge slag dump.
The ore refining industry is not the only one who has waste products and by-products for which there is little or no commercial use. The paper industry has long recycled paper for use in the manufacture of new paper to the greatest extent possible. However, each reuse of the paper results in a breakdown of the fibers which make up the paper and ultimately when the fibers become too short, it cannot be reused. At the present time it is not possible to reuse newsprint in the manufacture of new paper except to a very limited extent. Typically, newsprint is disposed of either by burning or by its use in sanitary landfills. One comparatively recent use for newsprint is in the manufacture of insulation for homes and offices. However, the quantity of newsprint which is consumed by this use is extremely small and its use has recently come under severe criticism because of the safety hazards involved in the use of highly flammable cellulose products as insulation.
Other industries such as the forestry industry, rubber industry and coal mining industry have similar types of by-products or waste products for which there is presently no commercial demand. For example, the coal industry collects vast quantities of coal fines for which there is little present use. The coal is typically contained in a slurry with water, termed "black water" by the industry, which must be held in settling ponds to separate the coal fines from the water before the water can be discharged to the streams. Since this water is often highly acidic, it should be treated prior to its discharge and indeed the Environmental Protection Agency is presently concerned with the high acidity of such waste water. Like the coal industry, the forestry industry also has a significant quantity of by-products for which there is presently little or no commercial demand. Typical by-products are tree bark, sawdust and wood fibers, which are produced in the manufacture of wood products.
While at the present time there is little or no demand for waste products such as those described above and others of similar character, there is a presently existing need for a technique which allows one to revegetate the areas which have been strip mined in this country as well as for better techniques for reforesting those areas from which lumber has been harvested. At the present time it is very difficult to revegetate a strip mined area because most of the topsoil has been removed and the soil which remains is very hard and dense and does not provide a good growing surface for grasses or seedlings. Synthetic seed beds are useful in such difficult environments to provide a good start for seedlings and the like. As in the case of reclaimed strip mines, the site may be too firmly packed in the soil, too impervious for direct seeding, although plants once vigorously growing, will establish themselves in such soil. A synthetic seed bed may give the seedlings the required head start to flourish in such a hostile environment.
When seeds spout, the tiny rootlets are very vulnerable to damage from the hard soil or from a very hard rain. The microscopic root hairs of the rootlet must remain in contact with liquid water while at the same time having access to oxygen. The rootlets must have room for growth until they have grown strong enough to penetrate the firm soil while at the same time being protected from drying out or drowning or from physical dislodgement. Properly designed synthetic seed beds will provide the necessary environment.
Prior art techniques exist for overcoming some of the problems which are encountered in reseeding areas such as strip mines. However, none of the products presently available are capable of providing the necessary environment for guaranteeing vigorous plant growth while at the same time having the necessary physical attributes of protecting the growing plant from the vagaries of our environment.
With the oncoming of the energy crisis, the use of fireplaces and stoves to serve a functional as well as decorative purpose has gained wide spread acceptance. The renewed interest in the use of stoves and fireplaces has placed a strain on the supply of suitable fuels for these devices. In many of the metropolitan areas it is difficult to obtain aged wood to burn in these devices and the costs are quite often prohibitive, making the economics of using stoves and fireplaces as a supplemental heat source unattractive. While there is often a shortage of high quality fuel for such devices, the coal industry has significant quantities of coal dust for which there is presently little or no commercial market. It would obviously be desirable to convert this coal dust into a product which could be burned in a stove or fireplace to provide not only aesthetic appeal but also a supplemental heat source.
Accordingly, a need exists for a technique for converting the waste products and by-products of industry into useful commercial articles which fill existing needs.